Advances in magnetic nanoparticle-based detection of bacteria: Strategies, challenges, and future perspectives

Abstract

Bacterial diseases and their different forms of severity affect millions of people worldwide at any given time. Conventional bacterial detection methods, though widely used, are limited by long processing times, reliance on skilled personnel, sophisticated equipment, and poor suitability for point-of-care use. Thus, there is a constant need for advanced bacterial detection methods and techniques that will produce rapid results so that early diagnosis of diseases can be done. It will also help in ensuring the safety of food and environmental samples, which are the most common sources of bacterial diseases. This is where magnetic nanoparticles (MNPs) prove to be valuable and effective. Their properties of superparamagnetism, high surface-to-volume ratio, biocompatibility and the convenience of functionalization make MNPs a reliable and advanced tool for rapid bacterial detection. This review provides an overview of the current bacterial detection mechanisms using MNPs and how different strategies for their compositional or surface modifications can improve sensitivity and optimize the rate of limit-of-detection (LOD). Real-time application of MNPs for bacterial detection in samples such as food, environmental sources, urine, blood, and other body fluids or cells has also been studied in this review. It also discusses the recent developments incorporating MNPs in other detection techniques, such as CRISPR, and explores how artificial intelligence (AI) can be used to build smart detection systems.